RFID is a non-contact automatic identification technology, which identifies target object automatically through the radio frequency signal and acquires related data. The identification does not need human intervention, this technology has advantages including quick and convenient operation, long service life, long reading distance and large capacity of data storage; besides, the data on the tag can be encrypted and the information stored can also be changed conveniently.
As a data carrier, the electronic tag can be used for identifier recognition, article tracking and information acquisition. At home and abroad, the electronic tag has been used widely applied to many fields. The RFID system formed by an electronic tag, a reader-writer, an antenna and application software is connected directly with the relevant information management system. Every article can be tracked accurately, and this kind of information management system can bring many benefits to customers, including real-time data acquisition, safe data access channel and acquisition of all product information in offline state. Therefore, the RFID technology has been widely applied to many fields like industrial and commercial automation.
In order to enable RFID tag to work in highly humid severe environment of dust pollution, the tag chip and antenna are arranged in the protection space formed by housing structure for placing tag, thus to reach a certain protection level standard; for example, IP68 (ingress protection 68) standard protection level. The American patent US 2010/0259393A1 discloses an RFID tag structure, in which the RFID tag is placed in a capsule type space formed by two shells. The above structure realizes good improvement on waterproof and dustproof property of the RFID tag. Moreover, in actual use, a waterproof sealing rubber is used to seal and strengthen the joint part of the two shells.
However, when the RFID tag with waterproof hermitic housing is placed in a high-temperature serve environment, temperature of the air inside the external housing raises, which causes expansion of the air and generation of big tension, so the air pressure in the housing is higher than that of the air outside the housing; specifically when the temperature outside of the housing is higher than 300° C., (for example, on the paint spraying line of automobile production, temperature of housing of the RFID tag to record process information and process operation information), if the pressure inside cannot be eliminated, it is easy to deform the two housings with waterproof sealing structure, and even crack the structure; as a result, the RFID tag placed in the space formed by the encapsulation structure of two housings can be damaged.
Therefore, in consideration of application of RFID tag in special environment, for example, management and tracking of automobile industry, and oil & gas, the RFID tag product that can resist super high temperature (higher than 250° C.) and meet the IP68 protection standard.